This invention relates to undersea cable and manufacturing methods, and, particularly to underwater fiber-optic cable and methods.
There is an ever-increasing need for the transmission of data, voice, video and other signals under water.
One source of such need is the proliferation of offshore oil exploration and production rigs, and the need for more bandwidth to support remotely controlled equipment, geological and scientific business and personal contacts, including data collection, and telecommunications for personnel on manned platforms.
It has been attempted to provide a fiber-optic communication network linking numerous off-shore oil facilities with land-based stations. However, the undersea portion of such a network has presented numerous challenges and problems.
One problem with prior undersea fiber-optic cable communication lines lies in the insufficiency of the cable. Often, the cable provided in the past has not been sufficiently robust. If sufficiently robust, it has been undesirably heavy and expensive.
Accordingly, one of the objects of the invention is to provide an underwater fiber-optic cable which solves or alleviates the foregoing problems, and particularly a cable which is relatively light-weight but robust and flexible, and resistant to environmental attacks, such as by chewing fish and other sea life.
In accordance with the present invention, the foregoing objectives are satisfied by the provision of a cable having a fiber-optic core with a plurality of metal wires wrapped around the core to give strength and cut-resistance, and a tensioned metal and plastic laminate tape, wrapped about the wires under relatively high tension. The resulting tensioned laminate is believed to compress the wires and core and hold them together while not adding unacceptably to the cable diameter, and to otherwise improve the cable.
In one aspect of the invention, a malleable metal-containing tape is wrapped about a layer of strength members surrounding a fiber-optic core to provide a relatively strong, cut and corrosion-resistant underwater cable.
The cable is highly advantageous because it exhibits relatively low strain per unit of tension applied to the cable, thus making it possible to use reduced quantities of strength members and/or relatively small diameter cable so as to reduce the cost, weight and volume occupied by reels of the cable. This facilitates laying the cable on or under the surface of the floor of the body of water in which it is used.
The cable of the invention has special utility when used with an underwater dispenser which gives the cable a reverse twist to minimize tanglingxe2x80x94the cable is sufficiently flexible to endure the reverse twist and sharp bends often experienced during dispensing.
The foregoing and other objects and advantages of the invention will be set forth in or made apparent from the following description and drawings.